{
"openapi": "3.0.2",
"info": {
"title": "Klaviyo API (Beta)",
"version": "2026-07-15.pre",
"description": "The Klaviyo REST API. Please visit https://developers.klaviyo.com for more details.",
"contact": {
"name": "Klaviyo Developer Experience Team",
"email": "developers@klaviyo.com",
"url": "https://developers.klaviyo.com"
},
"termsOfService": "https://www.klaviyo.com/legal/api-terms",
"license": {
"name": "License",
"url": "https://www.klaviyo.com/legal"
}
},
"servers": [
{
"url": "https://a.klaviyo.com",
"description": "Production"
}
],
"security": [
{
"Klaviyo-API-Key": []
}
],
"paths": {
"/api/text-messaging-senders": {
"post": {
"operationId": "create_text_messaging_sender_beta",
"summary": "Create Text Messaging Sender",
"description": "\n > \ud83d\udea7 This endpoint is in beta and subject to change.\n >\n > A beta revision header (2026-07-15.pre) is required to use our beta APIs. Klaviyo APIs in beta are not intended for use in production. See our [versioning and deprecation policy](https://developers.klaviyo.com/en/docs/api_versioning_and_deprecation_policy) for more information.\n\nCreate a sender and submit its initial registration.\n\nA toll-free number is provisioned in all supported regions (US + CA), so\nthe response is the sender for the requested country and the\nsibling-region sender also appears in list/retrieve.
*Rate limits*:
Burst: `10/s`
Steady: `150/m`\n\n**Scopes:**\n`sender-config:write`\n\n[OpenAPI Spec](https://raw.githubusercontent.com/klaviyo/openapi/main/openapi/beta/apis/create_text_messaging_sender_beta.json)",
"parameters": [
{
"name": "fields[text-messaging-sender-registration]",
"in": "query",
"description": "For more information please visit https://developers.klaviyo.com/en/v2026-07-15.pre/reference/api-overview#sparse-fieldsets",
"required": false,
"schema": {
"type": "array",
"items": {
"type": "string",
"enum": [
"created_at",
"decided_at",
"failures",
"id",
"status",
"submitted_at",
"updated_at"
]
}
},
"explode": false
},
{
"name": "fields[text-messaging-sender]",
"in": "query",
"description": "For more information please visit https://developers.klaviyo.com/en/v2026-07-15.pre/reference/api-overview#sparse-fieldsets",
"required": false,
"schema": {
"type": "array",
"items": {
"type": "string",
"enum": [
"created_at",
"forwarding_number",
"id",
"sender_details",
"sender_details.country",
"sender_identifier",
"sender_type",
"status"
]
}
},
"explode": false
},
{
"name": "include",
"in": "query",
"description": "For more information please visit https://developers.klaviyo.com/en/v2026-07-15.pre/reference/api-overview#relationships",
"schema": {
"type": "array",
"items": {
"type": "string",
"enum": [
"text-messaging-sender-registration"
]
}
},
"explode": false
},
{
"name": "revision",
"in": "header",
"description": "API endpoint revision (format: YYYY-MM-DD[.suffix])",
"required": true,
"schema": {
"type": "string",
"default": "2026-07-15.pre"
}
}
],
"requestBody": {
"description": "Create a text-messaging sender.",
"required": true,
"content": {
"application/vnd.api+json": {
"schema": {
"$ref": "#/components/schemas/TextMessagingSenderCreateQuery"
}
}
}
},
"responses": {
"201": {
"description": "Success",
"content": {
"application/vnd.api+json": {
"schema": {
"$ref": "#/components/schemas/PostTextMessagingSenderResponse"
}
}
}
},
"4XX": {
"$ref": "#/components/responses/ClientError"
},
"5XX": {
"$ref": "#/components/responses/ServerError"
}
},
"tags": [
"Beta APIs"
],
"x-klaviyo-pre-release": "BETA",
"x-klaviyo-ratelimit": {
"burst": "10/s",
"steady": "150/m"
},
"x-klaviyo-scopes": [
"sender-config:write"
],
"x-klaviyo-subtag": "Text Messaging"
}
}
},
"components": {
"responses": {
"ClientError": {
"description": "Client Error",
"content": {
"application/vnd.api+json": {
"schema": {
"type": "object",
"properties": {
"errors": {
"type": "array",
"items": {
"type": "object",
"required": [
"id",
"code",
"title",
"detail"
],
"properties": {
"id": {
"type": "string"
},
"code": {
"type": "string"
},
"title": {
"type": "string"
},
"detail": {
"type": "string"
},
"source": {
"type": "object",
"properties": {
"pointer": {
"type": "string"
},
"parameter": {
"type": "string"
}
}
}
}
}
}
},
"required": [
"errors"
]
}
}
}
},
"ServerError": {
"description": "Server Error",
"content": {
"application/vnd.api+json": {
"schema": {
"type": "object",
"properties": {
"errors": {
"type": "array",
"items": {
"type": "object",
"required": [
"id",
"code",
"title",
"detail"
],
"properties": {
"id": {
"type": "string"
},
"code": {
"type": "string"
},
"title": {
"type": "string"
},
"detail": {
"type": "string"
},
"source": {
"type": "object",
"properties": {
"pointer": {
"type": "string"
},
"parameter": {
"type": "string"
}
}
}
}
}
}
},
"required": [
"errors"
]
}
}
}
}
},
"schemas": {
"Address": {
"type": "object",
"properties": {
"street_address_1": {
"description": "Street address line 1.",
"type": "string",
"example": "125 Summer Street"
},
"city": {
"description": "City.",
"type": "string",
"example": "Boston"
},
"region": {
"description": "State, province, or region.",
"type": "string",
"example": "MA"
},
"postal_code": {
"description": "Postal code.",
"type": "string",
"example": "02110"
},
"country": {
"description": "ISO 3166-1 alpha-2 country code for the business address.",
"type": "string",
"example": "US"
},
"street_address_2": {
"description": "Street address line 2.",
"type": "string",
"example": "Suite 400",
"nullable": true
}
},
"required": [
"street_address_1",
"city",
"region",
"postal_code",
"country"
]
},
"AgentHints": {
"description": "Optional hints emitted by the API for agent callers",
"type": "object",
"properties": {
"next_steps": {
"description": "Suggested follow-up actions for agents to take after this response",
"type": "array",
"items": {
"type": "string"
}
}
}
},
"Failure": {
"type": "object",
"properties": {
"detail": {
"description": "Human-readable description of the failure.",
"type": "string"
}
},
"required": [
"detail"
]
},
"ObjectLinks": {
"type": "object",
"properties": {
"self": {
"type": "string",
"format": "uri"
}
},
"required": [
"self"
]
},
"PostTextMessagingSenderResponse": {
"type": "object",
"properties": {
"data": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderEnum"
},
"id": {
"description": "The unique identifier for this text-messaging sender.",
"type": "string",
"example": "01HX2Z8RG7Y4PWFQK3V0M5N1B7"
},
"attributes": {
"type": "object",
"properties": {
"sender_type": {
"description": "The kind of sender (e.g. toll-free, short-code, long-code, alpha).",
"type": "string",
"enum": [
"alpha",
"long_code",
"short_code",
"toll_free",
"vanity_short_code"
]
},
"sender_details": {
"description": "Attributes specific to the sender's type.",
"$ref": "#/components/schemas/TollFreeSenderResponseDetails"
},
"status": {
"description": "The lifecycle status of this sender.",
"type": "string",
"enum": [
"active",
"pending_registration",
"registering",
"registration_failed",
"suspended"
]
},
"created_at": {
"description": "ISO8601 timestamp when the sender was created.",
"type": "string",
"format": "date-time",
"example": "2026-05-19T14:30:00Z"
},
"forwarding_number": {
"description": "E.164 phone number inbound voice calls are forwarded to. Null when no forwarding is configured.",
"type": "string",
"nullable": true
},
"sender_identifier": {
"description": "The sender's outbound address \u2014 E.164 phone number for phone-number senders. Null while the sender is still pending registration.",
"type": "string",
"example": "+18005551234",
"nullable": true
}
},
"required": [
"sender_type",
"sender_details",
"status",
"created_at"
]
},
"relationships": {
"type": "object",
"properties": {
"text-messaging-sender-registration": {
"type": "object",
"properties": {
"data": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderRegistrationEnum"
},
"id": {
"type": "string"
}
},
"required": [
"type",
"id"
]
},
"links": {
"$ref": "#/components/schemas/RelationshipLinks"
}
}
}
}
},
"links": {
"$ref": "#/components/schemas/ObjectLinks"
}
},
"required": [
"type",
"id",
"attributes",
"links"
]
},
"included": {
"type": "array",
"items": {
"$ref": "#/components/schemas/TextMessagingSenderRegistrationResponseObjectResource"
}
},
"links": {
"$ref": "#/components/schemas/ObjectLinks"
},
"meta": {
"$ref": "#/components/schemas/ResponseMeta"
}
},
"required": [
"data"
]
},
"RelationshipLinks": {
"type": "object",
"properties": {
"self": {
"type": "string",
"format": "uri"
},
"related": {
"type": "string",
"format": "uri"
}
},
"required": [
"self",
"related"
]
},
"ResponseMeta": {
"description": "Response-level metadata",
"type": "object",
"properties": {
"agent_hints": {
"$ref": "#/components/schemas/AgentHints"
}
}
},
"TextMessagingSenderCreateQuery": {
"type": "object",
"properties": {
"data": {
"$ref": "#/components/schemas/TextMessagingSenderCreateQueryResourceObject"
}
},
"required": [
"data"
]
},
"TextMessagingSenderCreateQueryResourceObject": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderEnum"
},
"attributes": {
"type": "object",
"properties": {
"sender_type": {
"description": "The kind of sender to create. Must be `toll_free` in v1.",
"type": "string",
"enum": [
"alpha",
"long_code",
"short_code",
"toll_free",
"vanity_short_code"
]
},
"sender_details": {
"description": "Attributes specific to the requested `sender_type`.",
"$ref": "#/components/schemas/TollFreeSenderDetails"
},
"text-messaging-sender-registration": {
"description": "Toll-free verification submitted with the new sender.",
"type": "object",
"properties": {
"data": {
"$ref": "#/components/schemas/TollFreeRegistrationDetailsResourceObject"
}
},
"required": [
"data"
]
},
"forwarding_number": {
"description": "E.164 phone number to forward inbound voice calls to. Optional.",
"type": "string",
"example": "+15557654321",
"nullable": true
}
},
"required": [
"sender_type",
"sender_details",
"text-messaging-sender-registration"
]
}
},
"required": [
"type",
"attributes"
]
},
"TextMessagingSenderEnum": {
"type": "string",
"enum": [
"text-messaging-sender"
]
},
"TextMessagingSenderRegistrationEnum": {
"type": "string",
"enum": [
"text-messaging-sender-registration"
]
},
"TextMessagingSenderRegistrationResponseObjectResource": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderRegistrationEnum"
},
"id": {
"description": "The unique identifier for this sender registration.",
"type": "string",
"example": "01HX2Z8RG7Y4PWFQK3V0M5N1C8"
},
"attributes": {
"type": "object",
"properties": {
"status": {
"description": "The lifecycle status of this sender registration.",
"type": "string",
"enum": [
"action_required",
"approved",
"in_review",
"rejected"
]
},
"failures": {
"description": "Failures recorded against this registration.",
"type": "array",
"items": {
"$ref": "#/components/schemas/Failure"
}
},
"created_at": {
"description": "ISO8601 timestamp when the registration was created.",
"type": "string",
"format": "date-time",
"example": "2026-05-19T14:30:00Z"
},
"updated_at": {
"description": "ISO8601 timestamp when the registration was last updated.",
"type": "string",
"format": "date-time",
"example": "2026-05-19T14:30:00Z"
},
"submitted_at": {
"description": "ISO8601 timestamp when the registration was submitted. Null until the customer submits the registration.",
"type": "string",
"format": "date-time",
"example": "2022-11-08T00:00:00+00:00",
"nullable": true
},
"decided_at": {
"description": "ISO8601 timestamp when the registration was approved or rejected. Null until the carrier returns a decision.",
"type": "string",
"format": "date-time",
"example": "2022-11-08T00:00:00+00:00",
"nullable": true
}
},
"required": [
"status",
"failures",
"created_at",
"updated_at"
]
},
"relationships": {
"type": "object",
"properties": {
"text-messaging-sender": {
"type": "object",
"properties": {
"data": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderEnum"
},
"id": {
"type": "string"
}
},
"required": [
"type",
"id"
]
},
"links": {
"$ref": "#/components/schemas/RelationshipLinks"
}
}
}
}
},
"links": {
"$ref": "#/components/schemas/ObjectLinks"
}
},
"required": [
"type",
"id",
"attributes",
"links"
]
},
"TollFreeRegistrationDetailsResourceObject": {
"type": "object",
"properties": {
"type": {
"$ref": "#/components/schemas/TextMessagingSenderRegistrationEnum"
},
"attributes": {
"type": "object",
"properties": {
"first_name": {
"description": "Contact first name.",
"type": "string",
"example": "Jane"
},
"last_name": {
"description": "Contact last name.",
"type": "string",
"example": "Doe"
},
"phone_number": {
"description": "Contact phone number in E.164 format.",
"type": "string",
"example": "+15551234567"
},
"email": {
"description": "Contact email address.",
"type": "string",
"example": "jane@example.com"
},
"address": {
"description": "Business postal address for the registration.",
"$ref": "#/components/schemas/Address"
},
"business_type": {
"description": "Legal structure of the business.",
"type": "string",
"enum": [
"GOVERNMENT",
"NON_PROFIT",
"PRIVATE_PROFIT",
"PUBLIC_PROFIT",
"SOLE_PROPRIETOR"
]
},
"business_name": {
"description": "Legal business name.",
"type": "string",
"example": "Acme Corp"
},
"business_website": {
"description": "Public website URL for the business.",
"type": "string",
"example": "https://acme.example.com"
},
"doing_business_as": {
"description": "DBA name if different from the legal business name.",
"type": "string",
"nullable": true
},
"business_registration_country": {
"description": "ISO 3166-1 alpha-2 country in which the business is registered. Required for all businesses; must be `US` for a sole proprietor omitting the registration authority and number.",
"type": "string",
"example": "US",
"nullable": true
},
"business_registration_authority": {
"description": "Authority that issued the business registration number. Required unless the business is a US sole proprietor without a registration number.",
"type": "string",
"enum": [
"ABN",
"ACN",
"BRN",
"CBN",
"CIF",
"CNPJ",
"CRN",
"EIN",
"NEQ",
"NIF",
"NZBN",
"OTHER",
"PROVINCIAL_NUMBER",
"SIREN",
"SIRET",
"UID",
"USt-IdNr",
"VAT"
],
"nullable": true
},
"business_registration_number": {
"description": "Business registration number. Required unless the business is a US sole proprietor.",
"type": "string",
"nullable": true
}
},
"required": [
"first_name",
"last_name",
"phone_number",
"email",
"address",
"business_type",
"business_name",
"business_website"
]
}
},
"required": [
"type",
"attributes"
]
},
"TollFreeSenderDetails": {
"type": "object",
"properties": {
"country": {
"description": "ISO 3166-1 alpha-2 country code for the sender. Supported values: `US` and `CA`.",
"type": "string",
"example": "US",
"enum": [
"CA",
"US"
]
}
},
"required": [
"country"
]
},
"TollFreeSenderResponseDetails": {
"type": "object",
"properties": {
"country": {
"description": "ISO 3166-1 alpha-2 country code the sender is provisioned in.",
"type": "string",
"example": "US"
}
},
"required": [
"country"
]
}
},
"securitySchemes": {
"Klaviyo-API-Key": {
"type": "apiKey",
"in": "header",
"name": "Authorization",
"description": "Private key authentication for /api/ endpoints is performed by setting the `Authorization` header to `Klaviyo-API-Key your-private-api-key`
For more information please visit https://developers.klaviyo.com/en/v2026-07-15.pre/reference/api-overview#authentication",
"x-default": "Klaviyo-API-Key your-private-api-key"
}
}
},
"tags": [
{
"name": "Beta APIs",
"description": "beta apis"
}
]
}